• IMMUNE NETWORK
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• v.20 no.6
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• pp.49.1-49.15
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• 2020

C-C chemokine receptor type 5 (CCR5) regulates the trafficking of various immune cells to sites of infection. In this study, we showed that expression of CCR5 and its ligands was rapidly increased in the kidney after systemic Candida albicans infection, and infected CCR5^-/- mice exhibited increased mortality and morbidity, indicating that CCR5 contributes to an effective defense mechanism against systemic C. albicans infection. The susceptibility of CCR5^-/- mice to C. albicans infection was due to impaired fungal clearance, which in turn resulted in exacerbated renal inflammation and damage. CCR5-mediated recruitment of NK cells to the kidney in response to C. albicans infection was necessary for the anti-microbial activity of neutrophils, the main fungicidal effector cells. Mechanistically, C. albicans induced expression of IL-23 by CD11c⁺ dendritic cells (DCs). IL-23 in turn augmented the fungicidal activity of neutrophils through GM-CSF production by NK cells. As GM-CSF potentiated production of IL-23 in response to C. albicans, a positive feedback loop formed between NK cells and DCs seemed to function as an amplification point for host defense. Taken together, our results suggest that CCR5-mediated recruitment of NK cells to the site of fungal infection is an important step that underlies innate resistance to systemic C. albicans infection.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.134-134
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• 2017

Recently, host-induced gene silencing (HIGS) system has been successfully applied into development of resistant crops against insects, fungal and viral pathogens. To test HIGS-mediated resistance in rice against rice blast fungus, Magnaporthe oryzae, we first tested possibility of movement of small non-coding RNA from rice cells to rice blast fungus. The rice blast fungus expressing GFP transgene were inoculated to transgenic rice plants ectopically expressing dsRNAi construct targeting fungal GFP gene. Expression of dsRNAi construct for GFP gene in transgenic plants significantly suppressed GFP expression in infected fungal cells indicating that small RNAs generated in plant cells can move into infected fungal cells and efficiently suppress the expression of fungal GFP gene. Consistent with these results, expression of dsRNAi constructs against 3 fungal pathogenic genes of M. oryzae in transgenic rice specifically and efficiently suppressed not only the expression of fungal pathogenic genes, but also fungal infection. The conidia of M. oryzae applied on leaf sheath of transgenic rice expressing dsRNAs against 3 fungal pathogenic genes showed abnormal development of primary hyphae and malfunction of appressorium, which is consistent with the phenotypes of corresponding fungal knock-out mutants. Taken these results together, here, we suggest a novel strategy for development of antifungal crops by means of HIGS system.

• Biomolecules & Therapeutics
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• v.20 no.5
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• pp.433-445
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• 2012

During the course of evolution, animals encountered the harmful effects of fungi, which are strong pathogens. Therefore, they have developed powerful mechanisms to protect themselves against these fungal invaders. ${\beta}$-Glucans are glucose polymers of a linear ${\beta}$(1,3)-glucan backbone with ${\beta}$(1,6)-linked side chains. The immunostimulatory and antitumor activities of ${\beta}$-glucans have been reported; however, their mechanisms have only begun to be elucidated. Fungal and particulate ${\beta}$-glucans, despite their large size, can be taken up by the M cells of Peyer's patches, and interact with macrophages or dendritic cells (DCs) and activate systemic immune responses to overcome the fungal infection. The sampled ${\beta}$-glucans function as pathogen-associated molecular patterns (PAMPs) and are recognized by pattern recognition receptors (PRRs) on innate immune cells. Dectin-1 receptor systems have been incorporated as the PRRs of ${\beta}$-glucans in the innate immune cells of higher animal systems, which function on the front line against fungal infection, and have been exploited in cancer treatments to enhance systemic immune function. Dectin-1 on macrophages and DCs performs dual functions: internalization of ${\beta}$-glucan-containing particles and transmittance of its signals into the nucleus. This review will depict in detail how the physicochemical nature of ${\beta}$-glucan contributes to its immunostimulating effect in hosts and the potential uses of ${\beta}$-glucan by elucidating the dectin-1 signal transduction pathway. The elucidation of ${\beta}$-glucan and its signaling pathway will undoubtedly open a new research area on its potential therapeutic applications, including as immunostimulants for antifungal and anti-cancer regimens.

• The Plant Pathology Journal
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• v.38 no.3
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• pp.182-193
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• 2022

Turfgrass, the most widely grown ornamental crop, is severely affected by fungal pathogens including Sclerotinia homoeocarpa, Rhizoctonia solani, and Magnaporthe poae. At present, turfgrass fungal disease management predominantly relies on synthetic fungicide treatments. However, the extensive application of fungicides to the soil increases residual detection frequency, raising concerns for the environment and human health. The bacterial volatile compound, 2,3-butanediol (BDO), was found to induce plant resistance. In this study, we evaluated the disease control efficacy of a combination of stereoisomers of 2,3-BDO and commercial fungicides against turfgrass fungal diseases in both growth room and fields. In the growth room experiment, the combination of 0.9% 2R,3R-BDO (levo) soluble liquid (SL) formulation and 9% 2R,3S-BDO (meso) SL with half concentration of fungicides significantly increased the disease control efficacy against dollar spot and summer patch disease when compared to the half concentration of fungicide alone. In field experiments, the disease control efficiency of levo 0.9% and meso 9% SL, in combination with a fungicide, was confirmed against dollar spot and large patch disease. Additionally, the induction of defense-related genes involved in the salicylic acid and jasmonic acid/ethylene signaling pathways and reactive oxygen species detoxification-related genes under Clarireedia sp. infection was confirmed with levo 0.9% and meso 9% SL treatment in creeping bentgrass. Our findings suggest that 2,3-BDO isomer formulations can be combined with chemical fungicides as a new integrated tool to control Clarireedia sp. infection in turfgrass, thereby reducing the use of chemical fungicides.

• Korean Journal of Microbiology
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• v.19 no.3
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• pp.142-152
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• 1981

One hundred and thirteen healed pulmonary tuberculosis patients and 11 patients with other underlying diseases were studied for evidence of pulmonary fungal infection because of persisting hemoptysis or chronic cough. Rediological, mycological and serological investigations revealed that 54 out of 124 patients were evidently infected with one or more species of fungi. A. fumigatus was isolated from 4 out of 70 patients whose sera did not react with antigens from this fungus, while it was isolated from 43 out of 47 serological reactors to this fungus. Chest radiography showed a distinct fungus ball in a cyst of one patient and in a preformed cavity in the lung of 17 healed tuberculosis patients and two other patients. The latter two patients were infected with A.flavus. Two patients, who were under the long period of immunosuppressive therapy, apparently succumbed to invasive aspergillosia due to A.fumigatus. A single or dual infection with A. flavus, A. nidulans, A.nidulans var. latus, C. albicans, and P. boydii were noticed in some patients without mycetomal shadow on chest radiographs. Young mycelial extract (ME) of A.fumigatus detected antibody in 95.8 percent of the sera from patients infected with this fungus, while it was isolated from 43 out of 47 serological reactors to this fungus. Chest radiography showed a distinct fungus ball in a cyst of one patient and in a performed cavity in the lung of 17 healed tuberculosis patients and two other patients. The latter two patients were infected with A. flavus. Two patients, who were under the long period of immunosuppressive therapy, apparently succumbed to invasive aspergillosis due to A.fumigatus. A single or dual infection with A. flavus, A. nidulans, A. niduans var. latus, C. albicans, and P. boydii were noticed in some patients without mycetomal shadow on chest radiographs. Young mycelial extract (ME) of A.fumigatus detected antibody in 95.8 percent of the sera from patients infected with this fungus, while the commercial culture filtrate antigen (GL) yielded 78.7 per cent positive result. Culture filtrate antigen, however, was comparable with ME. There was no single antigen with which all the serum specimens reacted. Fractionation of ME resulted in a loss of some activity although it excluded substances that reacted with C-reactive protein in a loss of some activity although it excluded substances that reacted with C-reactive protein. Most reactive and specific precipitinogens distributed in the fraction (FB) which was precipitable at 75 percent saturation with ammonium sulfate and eluted in a second peak in order from gel-filtration and which contained mostly proteinic components. Glycoproteins or polysaccharides rich fractions (FA and ASI) were relatively less effective in detecting antibody. Demonstration of antibody in the serum from patients using a battery of fungal antigens and of etiologically related fungi from clinical specimens are very useful laboratory procedures for the diagnosis of pulmonary fungal infection which is a common complication of tuberculosis.

• Journal of Veterinary Clinics
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• v.40 no.5
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• pp.349-353
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• 2023

A 2-year-old outdoor, spayed, female Korean Jindo dog was referred for thoracic and abdominal masses. Diagnostic imaging revealed generalized lymphadenopathy and a significant amount of pleural effusion. The cytological evaluation of the pleural effusion and fine-needle aspiration of the mediastinal lymph nodes confirmed the presence of fungal hyphae. The histopathological examination of the mediastinal lymph nodes stained with Grocott's methenamine silver revealed fungal mycelia, and Aspergillus terreus was identified based on fungal DNA sequencing. Thus, the dog was diagnosed with disseminated canine aspergillosis caused by A. terreus. This case report describes a rare case of disseminated canine aspergillosis caused by A. terreus in a Korean Jindo dog.

• The Plant Pathology Journal
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• v.37 no.4
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• pp.347-355
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• 2021

Ripe rot caused by Botryosphaeria dothidea is one of the serious diseases of postharvest kiwifruit. In order to control ripe rot on Actinidia chinensis cultivar 'Zesy002', several commercial agrofungicides were selected by an antifungal test on an artificial medium. Furthermore, disease suppression by the selected fungicides was evaluated on the kiwifruit by inoculation with a conidial suspension of B. dothidea. On the artificial media containing boscalid + fludioxonil was shown to be the most effective antifungal activity. However, in the bio-test pyraclostrobin + boscalid and iminoctadinetris were the most effective agrochemicals on the fruit. On the other hand, the infection structures of B. dothidea on kiwifruit treated with pyraclostrobin + boscalid were observed with a fluorescent microscope. Most of the fungal conidia had not germinated on the kiwifruit treated with the agrochemicals whereas on the untreated fruit the fungal conidia had mostly germinated. Electron microscopy of the fine structures showed morphological changes to the conidia and branch of hyphae on the kiwifruit pre-treated with pyraclostrobin + boscalid, indicating its suppression effect on fungal growth. Based on this observation, it is suggested that ripe rot by B. dothidea may be suppressed through the inhibition of conidial germination on the kiwifruit treated with the agrochemicals.

• Journal of Korean Neurosurgical Society
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• v.56 no.5
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• pp.444-447
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• 2014

Cerebral phaeohyphomycosis (CP) is a very rare but serious form of central nervous system fungal infection that is caused by dematiaceous fungi. It is commonly associated with poor prognosis irrespective of the immune status of the patient. In this study, the authors describe the first case of CP in Korea that occurred in a 75-year-old man without immunodeficiency and showed favorable outcome after surgical excision and antifungal therapy. In addition, the authors herein review the literature regarding characteristics of this rare clinical entity with previously reported cases.

• The Plant Pathology Journal
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• v.30 no.2
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• pp.136-150
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• 2014

Although multiple transcription factors (TFs) have been characterized via mutagenesis to understand their roles in controlling pathogenicity and infection-related development in Magnaporthe oryzae, the causal agent of rice blast, if and how forkhead-box (FOX) TFs contribute to these processes remain to be characterized. Four putative FOX TF genes were identified in the genome of M. oryzae, and phylogenetic analysis suggested that two of them (MoFKH1 and MoHCM1) correspond to Ascomycota-specific members of the FOX TF family while the others (MoFOX1 and MoFOX2) are Pezizomycotina-specific members. Deletion of MoFKH1 (${\Delta}Mofkh1$) resulted in reduced mycelial growth and conidial germination, abnormal septation and stress response, and reduced virulence. Similarly, ${\Delta}Mohcm1$ exhibited reduced mycelial growth and conidial germination. Conidia of ${\Delta}Mofkh1$ and ${\Delta}Mohcm1$ were more sensitive to one or both of the cell cycle inhibitors hydroxyurea and benomyl, suggesting their role in cell cycle control. On the other hand, loss of MoFOX1 (${\Delta}Mofox1$) did not show any noticeable changes in development, pathogenicity, and stress response. Deletion of MoFOX2 was not successful even after repeated attempts. Taken together, these results suggested that MoFKH1 and MoHCM1 are important in fungal development and that MoFKH1 is further implicated in pathogenicity and stress response in M. oryzae.

• Korean Journal of Veterinary Service
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• v.40 no.1
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• pp.75-78
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• 2017

This report describes a case of pinnal fungal dermatitis caused by Arthroderma vanbreuseghemii in a Rex rabbit diagnosed by clinical signs, macro- and microscopic examination, molecular and phylogenetic analyses. This is the first description of natural A. vanbreuseghemii infection in rabbits in South Korea.